Cardiac biomarker responses following high-intensity interval and continuous exercise: the influence of ACE-I/D gene polymorphism and training status in men.

This study aimed to investigate the relationship between pre- and postexercise cardiac biomarker release according to athletic status (trained vs. untrained) and to establish whether the I/D polymorphism in the angiotensin-converting enzyme (ACE) gene had an influence on cardiac biomarkers release with specific regard on the influence of the training state. We determined cardiac troponin I (cTnI) and N-terminal pro-brain natriuretic peptide (NT-proBNP) in 29 trained and 27 untrained male soccer players before and after moderate-intensity continuous exercise (MICE) and high-intensity interval exercise (HIIE) running tests. Trained soccer players had higher pre (trained: 0.014 ± 0.007 ng/mL; untrained: 0.010 ± 0.005 ng/mL) and post HIIE (trained: 0.031 ± 0.008 ng/mL; untrained: 0.0179 ± 0.007) and MICE (trained: 0.030 ± 0.007 ng/mL; untrained: 0.018 ± 0.007) cTnI values than untrained subjects, but the change with exercise (ΔcTnI) was similar between groups. There was no significant difference in baseline and postexercise NT-proBNP between groups. NT-proBNP levels were elevated after both HIIE and MICE. Considering three ACE genotypes, the mean pre exercise cTnI values of the trained group (DD: 0.015 ± 0.008 ng/mL, ID: 0.015 ± 0.007 ng/mL, and II: 0.014 ± 0.008 ng/mL) and their untrained counterparts (DD: 0.010 ± 0.004 ng/mL, ID: 0.011 ± 0.004 ng/mL, and II: 0.010 ± 0.006 ng/mL) did not show any significant difference. To sum up, noticeable difference in baseline cTnI was observed, which was related to athletic status but not ACE genotypes. Neither athletic status nor ACE genotypes seemed to affect the changes in cardiac biomarkers in response to HIIE and MICE, indicating that the ACE gene does not play a significant role in the release of exercise-induced cardiac biomarkers indicative of cardiac damage in Iranian soccer players.NEW & NOTEWORTHY Our study investigated the impact of athletic status and angiotensin-converting enzyme (ACE) gene I/D polymorphism on cardiac biomarkers in soccer players. Trained players showed higher baseline cardiac troponin I (cTnI) levels, whereas postexercise ΔcTnI remained consistent across groups. N-terminal pro-brain natriuretic peptide increased after exercise in both groups, staying within normal limits. ACE genotypes did not significantly affect pre-exercise cTnI. Overall, athletic status influences baseline cTnI, but neither it nor ACE genotypes significantly impact exercise-induced cardiac biomarker responses in this population.

Kiwi-Inspired Rational Nanoarchitecture with Intensified and Discrete Magneto-Fluorescent Functionalities for Ultrasensitive Point-of-Care Immunoassay.

Fluorescent lateral flow immunoassays (FLFIA) is a well-established rapid detection technique for quantitative analysis. However, achieving accurate analysis of biomarkers at the pg mL-1 level using FLFIA still poses challenges. Herein, an ultrasensitive FLFIA platform is reported utilizing a kiwi-type magneto-fluorescent silica nanohybrid (designated as MFS) that serves as both a target-enrichment substrate and an optical signal enhancement label. The spatially-layered architecture comprises a Fe3O4 core, an endocarp-fibers like dendritic mesoporous silica, seed-like quantum dots, and a kiwi-flesh like silica matrix. The MFS demonstrates heightened fluorescence brightness, swift magnetic response, excellent size uniformity, and dispersibility in water. Through liquid-phase capturing and fluorescence-enhanced signal amplification, as well as magnetic-enrichment sample amplification and magnetic-separation noise reduction, the MFS-based FLFIA is successfully applied to the detection of cardiac troponin I that achieved a limit of detection at 8.4 pg mL-1, tens of times lower than those of previously published fluorescent and colorimetric lateral flow immunoassays. This work offers insights into the strategic design of magneto-fluorescent synergetic signal amplification on LFIA platform and underscores their prospects in high-sensitive rapid and on-site diagnosis of biomarkers.

Clinical relevance and advances in detection of translational biomarker cardiac troponin.

Cardiovascular diseases (CVD) are a range of diseases, pointing the functional hindrances in the heart and blood vessels of the human system that contributes to 48.6 % of the world's adult death rate. The diagnosis of CVD relies upon the Electro Cardio Gram (ECG) and detection of muscle markers such as troponins. Among the cardiac trio, Cardiac Troponin I (cTnI) weighing 23 KiloDalton (kDa) is a sorted biomarker for CVD. cTnI remains high in the blood after 1-2 weeks of myocardial damage. Testing of cTnI in CVD patients aids in diagnosis and risk stratification of the disease. Different determination systems including optical, electrochemical, and acoustic have been put forward for monitoring the cTnI which are Point of Care (POC) that promotes simple and sensitive detection of cTnI. The modern era has paved way to high-sensitivity Troponin I (hscTnI) devices that can detect up to 0.01 ng/ml in human blood/plasma/serum. Yet, the practice of hscTnI is impracticable due to cost inefficiency. Development of new hscTnI devices with minimal investment and maximal detection range will meet the global requirement. This review gives an over view on different detection systems of cardiac troponin I which stands as a translational detection molecule for CVDs.

Evaluation of the analytical and clinical performance of a new high-sensitivity cardiac troponin I assay: hs-cTnI (CLIA) assay.

OBJECTIVES: Cardiac troponin (cTn) is the key biomarker for diagnosis of acute coronary syndrome (ACS). We performed a complete assessment of the high-sensitivity cardiac troponin I (hs-cTnI) (CLIA) assay on the analytical performance and clinical diagnostic performance, which was compared with Abbott ARCHITECT hs-cTnI assay. METHODS: Sex-specific 99th percentile upper reference limits (URLs) were determined from a healthy population of 424 males and 408 females. High-sensitivity performance was assessed by examining the imprecision at sex-specific URLs and the detectable results above LoD in a cohort of healthy population. The diagnostic performance of the hs-cTnI (CLIA) assay was validated in a population of 934 patients with suspected ACS. RESULTS: The 99th percentile URLs were 15.3 ng/L for female, 31.3 ng/L for male and 24.2 ng/L for overall population. The total imprecision near the sex-specific 99th percentile URLs were <5 %. 76.74 % of females, 97.12 % of males and 86.69 % of overall population had cTnI values exceeding the LoD, which met the criteria of high-sensitivity troponin assay. No cross-reactivity or interference was identified. The diagnostic sensitivity, specificity, PPV, NPV, and AUC of hs-cTnI (CLIA) assay were 97.97 , 90.70, 79.02, 99.21 % and 0.9885, respectively, which were comparable to ARCHITECT hs-cTnI assay. CONCLUSIONS: hs-cTnI (CLIA) assay is a high-sensitivity troponin I method with high precision, sensitivity and specificity. The clinical diagnostic performance of hs-cTnI (CLIA) is comparable to the established ARCHITECT hs-cTnI assay. Mindray's hs-cTnI (CLIA) assay is an attractive alternative for diagnosis of myocardial infarction with a high level of accuracy and safety.

Prognostic significance of chronic myocardial injury diagnosed by three different cardiac troponin assays in patients admitted with suspected acute coronary syndrome.

OBJECTIVES: Chronic myocardial injury (CMI) is defined as stable concentrations of cardiac troponin T or I (cTnT or cTnI) above the assay-specific 99th percentile upper reference limit (URL) and signals poor outcome. The clinical implications of diagnosing CMI are unclear. We aimed to assess prevalence and association of CMI with long-term prognosis using three different high-sensitivity cTn (hs-cTn) assays. METHODS: A total of 1,292 hospitalized patients without acute myocardial injury had cTn concentrations quantified by hs-cTn assays by Roche Diagnostics, Abbott Diagnostics and Siemens Healthineers. The median follow-up time was 4.1 years. The prevalence of CMI and hazard ratios for mortality and cardiovascular (CV) events were calculated based on the URL provided by the manufacturers and compared to the prognostic accuracy when lower percentiles of cTn (97.5, 95 or 90), limit of detection or the estimated bioequivalent concentrations between assays were used as cutoff values. RESULTS: There was no major difference in prognostic accuracy between cTnT and cTnI analyzed as continuous variables. The correlation between cTnT and cTnI was high (r=0.724-0.785), but the cTnT assay diagnosed 3.9-4.5 times more patients with having CMI based on the sex-specific URLs (TnT, n=207; TnI Abbott, n=46, TnI Siemens, n=53) and had higher clinical sensitivity and AUC at the URL. CONCLUSIONS: The prevalence of CMI is highly assay-dependent. cTnT and cTnI have similar prognostic accuracy for mortality or CV events when measured as continuous variables. However, a CMI diagnosis according to cTnT has higher prognostic accuracy compared to a CMI diagnosis according to cTnI.

Photoelectrochemical immunoassay of cardiac troponin I based on ZnTCPP/CdIn2S4 type-II heterojunction and co-catalyzed precipitation biolabeling.

CdIn2S4 and zinc tetrakis(4-carboxyphenyl)porphyrin (ZnTCPP) were synthesized by hydrothermal method, and an organic dye-sensitized inorganic semiconductor ZnTCPP/CdIn2S4 type II heterojunction was constructed on a fluorine-doped tin oxide (FTO) substrate electrode. A sandwich immunostructure for signal-attenuation photoelectrochemical (PEC) detection of cardiac troponin I (cTnI) was constructed using the ZnTCPP/CdIn2S4/FTO photoanode and a horseradish peroxidase (HRP)-ZnFe2O4-Ab2-bovine serum albumin (BSA) immunolabeling complex. The bioenzyme HRP and the HRP-like nanozyme ZnFe2O4 can co-catalyze the oxidation of 4-chloro-1-naphthol (4-CN) by H2O2 to produce an insoluble precipitate on the photoanode, thus notably reducing the anodic photocurrent for quantitative determination of cTnI. Under the optimal conditions, the photocurrent at 0 V vs. SCE in 0.1 M phosphate buffer solution (pH 7.40) containing 0.1 M ascorbic acid was linear with the logarithm of cTnI concentration from 500 fg mL-1 to 50.0 ng mL-1, and the limit of detection (LOD, S/N = 3) is 0.15 pg mL-1. Spiked recoveries were 95.1% ~ 104% for assay of cTnI in human serum samples.

Elevated Cardiac Troponin I as a Mortality Predictor in Hospitalised COVID-19 Patients.

Background and Objectives: SARS-CoV-2 affects multiple organ systems, including the cardiovascular system, leading to immediate and long-term cardiovascular complications. Acute myocardial injury is one of the earliest and most common cardiac issues in the acute phase of COVID-19. This study aimed to evaluate the prognostic value of cardiac troponin I (cTnI) levels in predicting in-hospital mortality among hospitalised COVID-19 patients. Materials and Methods: A retrospective observational cohort study included 2019 adult patients hospitalised with a confirmed COVID-19 infection stratified by cTnI levels on admission into three groups: <19 ng/L (1416 patients), 19-100 ng/L (431 patients), and >100 ng/L (172 patients). Myocardial injury was defined as blood serum cTnI levels increased above the 99th percentile upper reference limit. Depersonalised datasets were extracted from digital health records. Statistical analysis included multivariable binary logistic and Cox proportional hazards regressions. Results: Overall, 29.87% of patients experienced acute myocardial injury, which development was associated with age, male sex, chronic heart failure, arterial hypertension, obesity, and chronic kidney disease. Among patients with cTnI levels of 19-100 ng/L, the odds ratio for requiring invasive mechanical ventilation was 3.18 (95% CI 2.11-4.79) and, for those with cTnI > 100 ng/L, 5.38 (95% CI 3.26-8.88). The hazard ratio for in-hospital mortality for patients with cTnI levels of 19-100 ng/L was 2.58 (95% CI 1.83-3.62) and, for those with cTnI > 100 ng/L, 2.97 (95% CI 2.01-4.39) compared to patients with normal cTnI levels. Conclusions: Increased cardiac troponin I, indicating myocardial injury, on admission is associated with a more adverse clinical disease course, including a higher likelihood of requiring invasive mechanical ventilation and increased risk of in-hospital mortality. This indicates cardiac troponin I to be a beneficial biomarker for clinicians trying to identify high-risk COVID-19 patients, choosing the optimal monitoring and treatment strategy for these patients.

Electro-immunosensor for ultra-sensitive determination of cardiac troponin I based on reduced graphene oxide and polytyramine.

This work reports the construction of a novel nanostructured immunosensor for detection of the troponin I biomarker (cTnI). Anti-troponin I antibody was anchored on the modified graphite electrode with reduced graphene oxide and polytyramine for detection of troponin I in serum samples. The performance of the electro-immunosensor was evaluated by differential pulse voltammetry. The immunosensor presented a wide work range, from 4 ng mL-1 to 4 pg mL-1 , whose detection limit (4 pg mL-1 ) is significantly lower than the basal level in human serum, and maintained 100% of response after 30 days of storage. Moreover, the immunosensor showed good selectivity for detection of cTnI in real sample containing interfering substances and specificity of response to cTnI in the serum of healthy and sick patients, and demonstrated the possibility of reuse for two consecutive analyses, in addition to using a simplified and inexpensive platform when compared to other devices, demonstrating them excellent potential for application in diagnosis in the early stages of acute myocardial infarction.

Longitudinal Changes in Cardiac Troponin and Risk of Heart Failure Among Black Adults.

BACKGROUND: Among Black adults, high-sensitivity cardiac troponin I (hs-cTnI) is associated with heart failure (HF) risk. The association of longitudinal changes in hs-cTnI with risk of incident HF, HF with reduced and preserved ejection fraction (HFrEF and HFpEF, respectively), among Black adults is not well-established. METHODS AND RESULTS: This study included Black participants from the Jackson Heart Study with available hs-cTnI data at visits 1 (2000-2004) and 2 (2005-2008) and no history of cardiovascular disease. Cox models were used to evaluate associations of categories of longitudinal change in hs-cTnI with incident HF risk. Among 2423 participants, 11.6% had incident elevation in hs-cTnI at visit 2, and 16.9% had stable or improved elevation (≤50% increase in hs-cTnI), and 4.0% had worsened hs-cTnI elevation (>50% increase). Over a median follow-up of 12.0 years, there were 139 incident HF hospitalizations (64 HFrEF, 58 HFpEF). Compared with participants without an elevated hs-cTnI, those with incident, stable or improved, or worsened hs-cTnI elevation had higher HF risk (adjusted hazard ratio 3.20 [95% confidence interval, 1.92-5.33]; adjusted hazard ratio 2.40, [95% confidence interval, 1.47-3.92]; and adjusted hazard ratio 8.10, [95% confidence interval, 4.74-13.83], respectively). Similar patterns of association were observed for risk of HFrEF and HFpEF. CONCLUSIONS: Among Black adults, an increase in hs-cTnI levels on follow-up was associated with a higher HF risk. LAY SUMMARY: The present study included 2423 Black adults from the Jackson Heart Study with available biomarkers of cardiac injury and no history of cardiovascular disease at visits 1 and 2. The majority of participants did not have evidence of cardiac injury at both visits (67.5%), 11.6% had evidence of cardiac injury only on follow-up, 14.5% had stable elevations, 4.0% had worsened elevations, and 2.4% had improved elevations of cardiac injury biomarkers during follow-up. Compared with participants without evidence of cardiac injury, those with new, stable, and worsened levels of cardiac injury had a higher risk of developing heart failure. TWEET: Among Black adults, persistent or worsening subclinical myocardial injury is associated with an elevated risk of HF.

Development of an ID-LC-MS/MS method using targeted proteomics for quantifying cardiac troponin I in human serum.

BACKGROUND: Cardiac troponin is a complex protein consisting of the three subunits I, T and C located in heart muscle cells. When the heart muscle is damaged, it is released into the blood and can be detected. Cardiac troponin I (cTnI) is considered the most reliable and widely accepted test for detecting and confirming acute myocardial infarction. However, there is no current standardization between the commercial assays for cTnI quantification. Our work aims to create a measurement procedure that is traceable to the International System of Units for accurately measuring cardiac cTnI levels in serum samples from patients. METHODS: The workflow begins with immobilizing anti-cTnI antibodies onto magnetic nanoparticles to form complexes. These complexes are used to isolate cTnI from serum. Next, trypsin is used to enzymatically digest the isolated cTnI. Finally, the measurement of multiple cTnI peptides is done simultaneously using isotope dilution liquid chromatography-tandem mass spectrometry (ID-LC-MS/MS). RESULTS: The maximum antibody immobilization was achieved by combining 1 mg of nanoparticles with 100 µg of antibody, resulting in an average of 59.2 ± 5.7 µg/mg of immobilized antibody. Subsequently, the anti-cTnI-magnetic nanoparticle complex was utilized to develop and validate a method for quantifying cTnI in human serum using ID-LC-MS/MS and a protein calibration approach. The analytical method was assessed regarding linearity and recovery. The developed method enables the quantification of cTnI from 0.7 to 24 µg/L (R > 0.996). The limit of quantification was 1.8 µg/L and the limit of detection was 0.6 µg/L. Intermediate precision was ≤ 9.6% and repeatability was 2.0-8.7% for all quality control materials. The accuracy of the analyzed quality control materials was between 90 and 110%. Total measurement uncertainties for target value assignment (n = 6) were found to be ≤ 12.5% for all levels. CONCLUSIONS: The analytical method demonstrated high analytical performance in accurately quantifying cardiac troponin I levels in human serum. The proposed analytical method has the potential to facilitate the harmonization of cTnI results between clinical laboratories, assign target values to secondary certified reference materials and support reliable measurement of cTnI.

Serum troponin is elevated in acute decompensation and acute-on-chronic liver failure and is associated with severity of liver disease and short-term mortality.

BACKGROUND: The role of high sensitive cardiac Troponin (hs-cTn) in patients with liver cirrhosis (LC) and liver-related acute events is not well established. AIM: To assess the prognostic performance of hs-cTn I in acute decompensation (AD) and acute-on-chronic liver failure (ACLF). METHODS: Two cohorts of consecutive patients, a derivation (retrospective) and a validation (prospective), were evaluated and 30-day-mortality was recorded. Hs-cTnI values were measured. Very low hs-cTnΙ (4 ng/L) was considered the cutoff-level. RESULTS: A total of 296 patients with LC [69.3% male, median age 57 (IQR 51-68) years, MELD score 19 (13-25), ACLF (29.4%), AD (48.3%), and without liver-related acute events (22.3%)] were included in the derivation cohort. The 66.2% of total patients had hs-cTnI ≥4 ng/L. Patients with hs-cTnI ≥4 ng/L were older and had more severe LC compared to those with <4ng/L. The multivariate analysis demonstrated that age (p < 0.001) and MELD (p = 0.001) were independent variables associated with elevated hs-cTnI after adjustment for age, sex and hepatic encephalopathy in total patients.When ACLF and AD were analyzed separately, the mortality was higher in patients with hs-cTnI ≥ 4 ng/L compared to lower values (log-rank p = 0.036 and p = 0.019, respectively). In multivariate analysis, MELD (p < 0.001) and hs-cTnI ≥4 ng/L (p = 0.032) were independent prognostic factors of mortality in ACLF/AD groups, after adjustment for age and sex. Similar results were obtained from the validation cohort (N = 148). CONCLUSIONS: hs-cTnI levels were higher in patients with severe liver disease. The low cutoff-point of 4 ng/L is accurate in ruling out non-survivors mainly in AD group.

Development of a system for detecting cardiac troponin I by background fluorescence quenching based on internal filtration effect.

The present study sought to develop a cardiac troponin I (cTnI) detection system based on background fluorescence quenching of internal filtration effect (IFE) and study the influence of IFE on the sensitivity of cTnI detection. Three nanogold materials were synthesized as fluorescence quenchers, and rhodamine 6 G (R6G) and Cy5 were used as fluorescence probes. Six experimental systems were established to detect cTnI in negative serum test solutions and clinical serum samples. The sensitivity of each system was compared to explore the contribution of IFE to the detection sensitivity of cTnI. When applied to negative serum test solutions, the R6G-nanogold material I system exhibited a superior detection effect for cTnI, with a limit of detection (LOD) of 0.15 ng ml-1. When applied to clinical serum samples, the Cy5-nanogold material Ⅲ system yielded a better detection effect for cTnI, with the lowest concentration of cTnI detected at 2 ng ml-1. The first and second internal filtering effects in the proposed system can be achieved simultaneously, effectively avoiding light absorption interference from clinical serum samples and enhancing the sensitivity of the background fluorescence quenching detection of cTnI.

Cardiac troponin measurement at the point of care: educational recommendations on analytical and clinical aspects by the IFCC Committee on Clinical Applications of Cardiac Bio-Markers (IFCC C-CB).

The International Federation of Clinical Chemistry and Laboarator Medicine (IFCC) Committee on Clinical Applications of Cardiac Bio-Markers (C-CB) has provided evidence-based educational resources to aid and improve the understanding of important analytical and clinical aspects of cardiac biomarkers. The present IFCC C-CB educational report focuses on recommendations for appropriate use, analytical performance, and gaps in clinical studies related to the use of cardiac troponin (cTn) by point of care (POC) measurement, often referred to as a point of care testing (POCT). The use of high-sensitivity (hs)-cTn POC devices in accelerated diagnostic protocols used in emergency departments or outpatient clinics investigating acute coronary syndrome has the potential for improved efficacy, reduction of length of stay and reduced costs in the health care system. POCT workflow integration includes location of the instrument, assignment of collection and testing responsibility to (non-lab) staff, instrument maintenance, in-service and recurrent training, quality control, proficiency assessments, discrepant result trapping, and troubleshooting and inventory management.

Quantitation of cardiac troponin I in cancer patients treated with immune checkpoint inhibitors: a case-control study.

OBJECTIVES: Immune checkpoint inhibitors (ICIs) cause a variety of toxicities, including immune-related adverse events (irAEs), but there are no biomarkers to predict their development. Guidelines recommend measuring circulating cardiac troponin I (cTnI) during ICI therapy to detect related cardiotoxicities. Moreover, elevated cTnI has also been associated with worse outcomes in non-cardiac patients, including cancer. Thus here, we investigated whether cTnI levels were higher in patients with irAEs. METHODS: The study consisted of three groups; 21 cancer patients undergoing ICI immunotherapies who presented with irAEs, four patients without irAEs, and 20 healthy controls. Patient samples were assessed at baseline (n=25), during ICI treatment (n=25, median=6 weeks of treatment) and at toxicity (n=6, median=13 weeks of treatment). In addition to blood high sensitivity cardiac troponin I (hs-cTnI), anti-thyroglobulin (TG) and anti-thyroid peroxidase (TPO) antibodies were also quantitated to detect thyroid dysfunction, constituting the second leading toxicity (23.8%) after pneumonitis (28.6%). RESULTS: Four patients with irAEs (n=4/21; 19%) and one without irAEs (n=1/4; 25%) showed higher hs-cTnI levels at any time-point; the remaining had physiological levels. None of these patients developed cardiotoxicity. Concurrent elevated levels of anti-thyroid antibodies and hs-cTnI were detected in one patient with thyroid dysfunction (n=1/5, 20%). However, these antibodies were also elevated in three patients (n=3/16, 19%) with non-thyroid irAEs and in up to 40% of healthy controls. CONCLUSIONS: hs-cTnI was not elevated in patients with irAEs, but larger studies are needed to confirm these observations.

Risk factors of preoperative myocardial injury in patients with gastrointestinal tumors.

BACKGROUND: Recent studies indicated that the prognosis of patients with gastrointestinal tumors is frequently influenced by its complications, notably myocardial injury. The main object is to investigate the occurrence and risk factors of myocardial injury in patients with gastrointestinal tumor. METHODS: 1126 patients who received gastrointestinal tumor related surgery from May 2018 to June 2020 in the Sixth Affiliated Hospital of Sun Yat-sen University were retrospectively collected and divided into the non-myocardial injury group and the myocardial injury group (high-sensitive cardiac troponin I (hs-cTnI) ≥ 0.028 ng/ml). The occurrence and risk factors of myocardial injury in patients with gastrointestinal tumor are analyzed. The influence of myocardial injury on the ICU detention time in gastrointestinal tumor patients is also studied. RESULTS: In total, 78 (6.93%) patients developed myocardial injuries. Compared with patients in the non-myocardial injury group, patients in the myocardial injury group have a higher prevalence of cardiovascular risk factors (including advanced age and higher smoking ratio), a higher prevalence of comorbidities (such as previous coronary artery disease, hypertension, atrium fibrillation and diabetes), and a higher rate of premedication (such as anticoagulation, ß-blocker, Angiotensin-converting enzyme inhibitor/Angiotensin II receptor blocker, and diuretic) (all with P-value < 0.05). In addition, patients in the myocardial injury group also presented with a higher revised cardiac risk index (Lee index), higher neutrophil granulocyte ratio, lower hemoglobin, and higher likelihood of impaired cardiac structure and function (all with P-value < 0.05). There was a trend of statistical significance in the ICU detention time between the myocardial injury group and the non-myocardial injury group (1[1,3] vs. 2[1,10], P = 0.064). In this study, there were 7 patients presented with clinical symptoms in the myocardial injury group (chest discomfort in 4 cases, non-compressive precordial chest pain in 1 case, dyspnea in 2 cases). In the multivariate analysis, advanced age, increased Lee index score, increased neutrophil granulocyte ratio, decreased left ventricular ejection fraction (LVEF), increased interventricular septum were independent risk factors for myocardial injury. CONCLUSION: In conclusion, advanced age, increased Lee index, increased neutrophil granulocyte ratio, decreased left ventricular ejection fraction, and increased ventricular septum were independent risk factors for preoperative myocardial injury in patients with gastrointestinal tumors. The proportion of clinical symptoms in gastrointestinal tumor patients with myocardial injury was low, indicating the necessity to closely monitor the cardiac status of individuals with gastrointestinal tumors.

The association of cardiac troponin and cardiovascular events in patients with concomitant heart failure preserved ejection fraction and atrial fibrillation.

BACKGROUND: Limited data are available for risk stratification in patients with atrial fibrillation (AF) and combined heart failure with preserved ejection fraction (HFpEF). We aimed to explore the prognostic utility of high-sensitivity cardiac troponin I (hs-cTnI) in patients with newly detected AF and concomitant HFpEF. METHODS: From August 2014 to December 2016, 2,361 patients with newly detected AF were polled in a retrospective single-center registry. Of which, 634 patients were eligible for HFpEF diagnosis (HFA-PEFF score ≥ 5) and 165 patients were excluded with exclusion criteria. Finally, 469 patients are classified into elevated or non-elevated hs-cTnI groups based on the 99th percentile upper reference limit (URL). The primary outcome was the incidence of major adverse cardiac and cerebrovascular events (MACCE) during follow-up. RESULTS: In 469 patients, 295 were stratified into the non-elevated hs-cTnI group (< 99th percentile URL of hs-cTnI) and 174 were placed in the elevated hs-cTnI group (≥ 99th percentile URL of hs-cTnI). The median follow-up period was 24.2 (interquartile range, 7.5-38.6) months. During the follow-up period, 106 patients (22.6%) in the study population experienced MACCE. In a multivariable Cox regression model, the elevated hs-cTnI group had a higher incidence of MACCE (adjusted hazard ratio [HR], 1.54; 95% confidence interval [CI], 1.08-2.55; p = 0.03) and coronary revascularization-caused readmission (adjusted HR, 3.86; 95% CI, 1.39-15.09; p = 0.02) compared with the non-elevated hs-cTnI group. The incidence of heart failure-caused readmission tended to occur more frequently in the elevated hs-cTnI group (8.5% versus 15.5%; adjusted HR, 1.52; 95% CI, 0.86-2.67; p = 0.08). CONCLUSIONS: One-fifth of patients with AF and concomitant HFpEF experienced MACCE during follow-up, and elevated hs-cTnI was independently associated with higher risk of MACCE, as driven by heart failure and revascularization-caused readmission. This finding suggested that hs-cTnI may be a useful tool in individualized risk stratification of future cardiovascular events in patients with AF and concomitant HFpEF.

Preoperative cardiac troponin I as a predictor of postoperative cardiac events in patients with end stage renal disease undergoing non-cardiac surgery.

We investigated if elevated cardiac troponin I (cTnI) serum levels before non-cardiac surgery were predictors of postoperative cardiac events in patients with end stage renal disease (ESRD) undergoing dialysis. In total, 703 consecutive patients with ESRD undergoing dialysis who underwent non-cardiac surgery were enrolled. Preoperative cTnI serum levels were measured at least once in all patients. The primary endpoint was defined as a composite of cardiac death, myocardial infarction (MI), and pulmonary edema during hospitalization or within 30 days after surgery in patients with a hospitalization longer than 30 days after surgery. Postoperative cardiac events occurred in 48 (6.8%) out of 703 patients (cardiac death 1, MI 18, and pulmonary edema 33). Diabetes mellitus (DM), previous ischemic heart disease, and congestive heart failure were more common in patients with postoperative cardiac events. Peak cTnI serum levels were higher in patients with postoperative cardiac event (180 ± 420 ng/L vs. 80 ± 190 ng/L, p = 0.008), and also elevated peak cTnI levels > 45 ng/L were more common in patients with postoperative cardiac events (66.8% vs. 30.5%, p < 0.001). Multivariate logistic regression analysis showed that DM (odds ratio [OR] 2.509, 95% confidence interval [CI] 1.178-5.345, p = 0.017) and serum peak cTnI levels ≥ 45 ng/L (OR 3.167, 95% CI 1.557-6.444, p = 0.001) were independent predictors for the primary outcome of cardiac death/MI/pulmonary edema. Moreover, cTnI levels ≥ 45 ng/L had an incremental prognostic value to the revised cardiac risk index (RCRI) (Chi-square = 23, p < 0.001), and to the combined RCRI and left ventricular ejection fraction (Chi-square = 12, p = 0.001). Elevated preoperative cTnI levels are predictors of postoperative cardiac events including cardiac death, MI, and pulmonary edema in patients with ESRD undergoing non-cardiac surgery.

Analysis and recognition of post-exercise cardiac state based on heart sound features and cardiac troponin I.

PURPOSE: Excessive intensity exercises can bring irreversible damage to the heart. We explore whether heart sounds can evaluate cardiac function after high-intensity exercise and hope to prevent overtraining through the changes of heart sound in future training. METHODS: The study population consisted of 25 male athletes and 24 female athletes. All subjects were healthy and had no history of cardiovascular disease or family history of cardiovascular disease. The subjects were required to do high-intensity exercise for 3 days, with their blood sample and heart sound (HS) signals being collected and analysed before and after exercise. We then developed a Kernel extreme learning machine (KELM) model that can distinguish the state of heart by using the pre- and post-exercise data. RESULTS: There was no significant change in serum cardiac troponin I after 3 days of load cross-country running, which indicates that there was no myocardial injury after the race. The statistical analysis of time-domain characteristics and multi-fractal characteristic parameters of HS showed that the cardiac reserve capacity of the subjects was enhanced after the cross-country running, and the KELM is an effective classifier to recognize HS and the state of the heart after exercise. CONCLUSION: Through the results, we can draw the conclusion that this intensity of exercise will not cause profound damage to the athlete's heart. The findings of this study are of great significance for evaluating the condition of the heart with the proposed index of heart sound and prevention of excessive training that causes damage to the heart.

Accuracy of Whole Blood Cardiac Troponin I in the Diagnosis of Childhood Heart Failure at the University College Hospital, Ibadan.

OBJECTIVE: To determine the accuracy of cardiac troponin I (cTnI), a marker of myocardial cell injury or necrosis, in correctly identifying heart failure in children. PATIENTS, MATERIALS, AND METHODS: This was a crosssectional study in which 45 children aged 12 years or below admitted into the paediatric wards of the University College Hospital, Ibadan, who, on evaluation with the Ibadan Childhood Heart Failure Index (ICHFI) had a score of ≥ 3, were consecutively recruited. Forty-five age- and sex-matched apparently healthy children with ICHFI score of <3 were similarly evaluated as controls. Demographic, clinical data and cTnI values were documented. Statistical analysis was done using IBM SPSS version 23. RESULTS: There was a strong positive correlation (0.592) between the whole blood cTnI values and ICHFI scores (rs = 0.592, P = 0.000). At a cut-off value of 0.07ng/ml, the whole blood cTnI had a sensitivity of 26.7%, specificity of 97.8%, a positive predictive value of 92.8% and a negative predictive value of 57.1%. The receiver operating characteristic curve plotted had an AUC of 0.800 at the 95% CI, 0.704 - 0.896; P < 0.001. CONCLUSION: Whole blood cTnI level is elevated in children in heart failure and may predict severity of the condition. Whole blood cTnI was found to be an accurate tool for the exclusion of heart failure in children and is therefore recommended for use in children with suspected heart failure for its rapid diagnosis.

OBJECTIF: Déterminer la précision de la troponine cardiaque I (cTnI), un marqueur de lésion ou de nécrose des cellules myocardiques, dans l'identification correcte de l'insuffisance cardiaque chez les enfants. PATIENTS, MATÉRIEL ET MÉTHODE: Il s'agit d'une étude transversale dans laquelle 45 enfants âgés de 12 ans ou moins admis dans les services pédiatriques de University College Hospital, Ibadan, qui, après évaluation avec Ibadan Childhood Heart Failure Index (ICHFI), avaient un score ≥ 3, ont été recrutés consécutivement. Quarante-cinq enfants apparemment sains, appariés selon l'âge et le sexe, avec un score ICHFI de <3 ont été évalués de la même manière en tant que témoins. Les données démographiques, cliniques et les valeurs de cTnI ont été documentées. L'analyse statistique a été réalisée à l'aide d'IBM SPSS version 23. RÉSULTATS: Il existe une forte corrélation positive (0,592) entre les valeurs de cTnI dans le sang total et les scores ICHFI (rs = 0,592, P = 0,000). À une valeur seuil de 0,07 ng/ml, le cTnI du sang total avait une sensibilité de 26,7 %, une spécificité de 97,8 %, une valeur prédictive positive de 92,8 % et une valeur prédictive négative de 57,1 %. La courbe caractéristique du récepteur tracée avait une AUC de 0,800 à l'IC de 95 %, 0,704 - 0,896 ; P < 0,001. CONCLUSION: Le taux de cTnI dans le sang total est élevé chez les enfants souffrant d'insuffisance cardiaque et peut prédire la gravité de la maladie. Le taux de cTnI dans le sang total s'est avéré être un outil précis pour l'exclusion de l'insuffisance cardiaque chez les enfants et il est donc recommandé de l'utiliser chez les enfants suspectés d'insuffisance cardiaque pour un diagnostic rapide de l'insuffisance cardiaque. Mots clés: Troponine cardiaque I, Insuffisance cardiaque chez l'Enfant, Ibadan.

Diagnostic evaluation of myeloperoxidase and Cardiac Troponin I in patients with acute coronary syndrome.

Objective: To evaluate the diagnostic accuracy of myeloperoxidase and cardiac troponin-I in patients with acute coronary syndrome. METHODS: The validity study was conducted from January to November 2018 at the Emergency and Pathology departments of the Punjab Institute of Cardiology, Lahore, and the Department of Pathology, Postgraduate Medical Institute, Lahore, Pakistan, and comprised adult patients of either gender who presented with complaint of constrictive pericarditis for testing the myeloperoxidase MPO and cardiac troponin-I concentrations. Data was obtained related to age, gender and electrocardiogram, and sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy were determined. Data was analysed using SPSS 20. RESULTS: Of the 62 patients with mean age 56.40+11.39 years, 49(79%) were males, 15(42%) were aged 51-60 years, 24(38.7%) had ST elevation, and 21(33.9%) had normal electrocardiogram. For myeloperoxidase, there were 13(21%) true positive, 39(63%) false negative and 10(16%) true negative cases. For cardiac troponin-I, there were 52(84%) true positive and 10(16%) true negative cases. The sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy values were 25%, 100%, 100%, 20.4% and 37%, respectively. Conclusion: Early prognostic assessment is necessary for application of proper treatment and management.